FIG. 1 illustrates a configuration of a conventional optical transmission module of this type described in Japanese Patent Application Laid Open No. 2006-59867 (issued on Mar. 2, 2006). An optical module 10 in that example includes a ferrule 11, an electrical interconnect (extraction electrode) 12, a surface light emitting device 13, optical-device mounting bumps 14, an optical fiber 15, a transparent resin 16 and a light-absorbing resin 17. An optical device driving IC 22 is mounted on an interconnection substrate 21 and the optical module 10 is mounted on the interconnection substrate 21 to form an optical transmission module. The optical device driving IC 22 and the optical module 10 in this example are flip-chip mounted. Connection bumps 23, a flip-chip mounting underfill material 24, and a heatsink 25 are also depicted in FIG. 1.
The optical fiber 15 is positioned and held in a ferrule 11. The electrical interconnect 12 is implemented by a thin-film electrode and formed by a method such as sputtering. The electrical interconnect 12 extends from the device mounting surface of the ferrule 11 onto one side surface of the ferrule 11 that faces the interconnection substrate 21. The surface light emitting device 13 is mounted on the electrical interconnect 12 through optical-device mounting bumps 14.
Required electronic interconnects (not depicted) are formed on the interconnection substrate 21 and the optical device driving IC 22 and the optical module 10 are mounted on the electrical interconnects through the connection bumps 23.